Ices in planet-forming disks: Self-consistent ice opacities in disk models

Context. In cold and shielded environments, molecules freeze out on dust grain surfaces to form ices such as H 2 O, CO, CO , CH 4 3 OH, NH . protoplanetary disks, conditions are present in the midplane regions beyond snowline, but exact radial vertical extension depend disk mass, geometry, stellar ultra-violet irradiation. Aims. The goal of this work is a computationally efficient method compute ice bare-grain opacities models consistently with chemistry investigate effect physico-chemical state optical appearance disk. Methods. A matrix Mie efficiencies pre-calculated for different species thicknesses, from which position dependent icy grains then interpolated. This implemented PRODIMO code by self-consistent solution local composition ices, obtained our chemical network. Results. Locally, opacity can change significantly, example, an increase factor more than 200 midplane, especially at wavelengths, due formation. mainly changes size distribution resulting However, since only optically thick disk, thermal structure does not significantly. For same reason, spectral energy distributions (SEDs) computed generally show faint emission features far-IR wavelengths. absorption seen edge-on orientation. assumption made how distributed across (ice power law) influences far-infrared millimeter slope SED. their strengths influenced law type chemistry. Our predict stronger observations that spatially resolve particularly absorption.